Process for making tracer compositions



nents of the combustible mixture are mixe Patented Feb. I 25, 1 930 WILLIAM S. l-IEITMANN, OF PHILADELPHIA, PENNSYLVANIA PROCESS FOR MAKING TRACER COMPOSITIONS No Drawing.

Application filed September 8, 1925. Serial No. 55,121.

(GRANTED UNDER THE ACT OF MARCH 3, 1883, AS AMENDED APRIL 30, 1928; 370 0. G. 757) The invention described herein may be manufacturedand used by or for the Government for governmental purposes Without the payment to me of any royalty thereon.

The subject of this invention is a combustible and method of preparing the same.

The invention relates more particularly to combustibles for use in tracer projectiles, signals, illuminants and the like.

The main objects of the invention are to secure a more intimate admixture of the various elements going to make up the combustible mixture to secure a more uniform product that will load or mold easily, and to waterproof the resulting combustible.

In carrying out the invention, the compotogether, and the binder, which may be calcium resinate or any other metal salt of resinous acids or a resinous ester or other suitable binder which may be used either as a fuel, as a binder, as a Waterproofing agent, or as any combination of these reasons, is dissolved in a suitable solvent, such as acetone or preferably a non-inflammable solvent, such as carbon tetrachloride, and is then added in its dissolved condition .to the mixed components of the combustible compound. After the ingredients are thus thoroughly mixed, the solvent is driven ofi, preferably by evaporation, and the resultant mass is ground and sieved or otherwise thoroughly mixed so that there is formed a powder, the separate and individual grains of which are coated or impregnated, or both, with the binder, which consequently is a more uniform burning mixture, one that is more easily loaded, and if a proper binder has been chosen, one which is almost completely nonhygroscopic. In loading or using such a resultant powder it is supposed that it will be forced by pressure into a container or will be molded by pressure into pellets or other shapes. By the use of this invention greater case will be secured in measuring this material, in pressing it as outlined above, and the resulting shapes or loaded containers will be waterproof. By the use of a proper binder, a pellet can be secured which has a hardness several times greater than that of lead, and

which will have sufiicient-tensile strength that it will not shatter with the shock of an explosion from a propelling charge when fired from a gun or rocket tube.

I claim:

1. The method of preparing a tracer mixture embodying mixing combustible ingredients, dissolving a metallic resinate in a sold tion thus obtained to the mixed ingredients and incorporating the same, driving oif the solvent, grinding and grading the resultant mass, then pressing the same to the desired form.

3. A method of preparing a tracer mixture embodying mixing the combustible ingredients, dissolving a metallic resinate in a solvent, adding the solution to the ingredients and incorporating the same, driving ofi the solvent then grinding and grading the re sultant mass.

WILLIAM S. HEITMANN.

the combustible in- 

